Prosecution Insights
Last updated: April 19, 2026
Application No. 18/265,341

HETERODIMERIC IGA FC CONSTRUCTS AND METHODS OF USE THEREOF

Non-Final OA §112
Filed
Jun 05, 2023
Examiner
MERTZ, PREMA MARIA
Art Unit
1674
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Zymeworks, Inc.
OA Round
1 (Non-Final)
72%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
99%
With Interview

Examiner Intelligence

Grants 72% — above average
72%
Career Allow Rate
539 granted / 754 resolved
+11.5% vs TC avg
Strong +36% interview lift
Without
With
+35.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
16 currently pending
Career history
770
Total Applications
across all art units

Statute-Specific Performance

§101
5.9%
-34.1% vs TC avg
§103
21.7%
-18.3% vs TC avg
§102
13.9%
-26.1% vs TC avg
§112
41.2%
+1.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 754 resolved cases

Office Action

§112
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Amended claims 1, 4-9, 11-12, 14-16, 18-20, 23, 25, 27, 30, 33-38, 41-44, (1/12/2024), original claims 2-3, 10, 24, 26, 31-32, 39-40, 45, and new claims 48-49, (1/12/2024), are pending and under consideration by the Examiner. Claims 13, 17, 21, 28-29, and 46-47, have been canceled. Information Disclosure Statement The information disclosure statements (IDS) submitted on 12/8/2025, 10/25/2024, and 1/22/2024, are in compliance with the provisions of 37 CFR 1.97 and have been considered by the examiner. Applicant is reminded of their duty to disclose to the Office all information known to the person to be material to patentability as defined in 37 CFR 1.56. As stated therein, “[e]ach individual associated with the filing and prosecution of a patent application has a duty of candor and good faith in dealing with the Office, which includes a duty to disclose to the Office all information known to that individual to be material to patentability as defined in this section”. Claim Rejections - 35 U.S.C. § 112 second paragraph 4. The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. 4a. Claims 1-12, 14-16, 18-20, 22-25, 27, 30-45, and 48-49 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention. Claim 1 is vague and indefinite for several reasons. Claim 1 is vague and indefinite because the claim references specific point mutations that are designated at specific amino acid residues within a parent polypeptide. However, the claims do not provide a parent polypeptide (amino acid sequence of specific SEQ ID NO), and therefore, it is impossible to determine where these substitutions would occur. Without a parent polypeptide (SEQ ID NO), there is no way to identify the correct residue for the substitution, to determine whether the parent polypeptide has the required base amino acid, and to confirm that the mutated polypeptide has the appropriate substituted amino acid (See specification, page 25, Table 5). The scope of the recited polypeptides is also indefinite because there is no way to determine at which position any given amino acid will be located. It is suggested that the claim be amended to recite the specific SEQ ID NO for the Fc polypeptide, with the specific mutations at the specific amino acid locations in the SEQ ID NO for the Fc polypeptides. Similarly, claims 4-12, 14-16, 18-20, 22, 25, 27, and 48 are vague and indefinite because the claims reference specific point mutations that are designated at specific amino acid residues within a parent polypeptide. However, the claims do not provide a parent polypeptide (amino acid sequence of specific SEQ ID NO), there is no way to identify the correct residue for the substitution. Claim 1, lines 2-5, 8, 12, are vague and indefinite because it recites “CH3 domain” however, without a reference SEQ ID NO, it is unclear what position this CH3 domain sequence is in the first Fc polypeptide and in the second Fc polypeptide. Similarly, claims 2-3, 9-12, 14-16, 18-20, 22-25, 27, 34-35, and 48 are vague and indefinite because they recite “CH3 domain” however, without a reference SEQ ID NO, it is unclear what position this CH3 domain sequence is in the first Fc polypeptide and in the second Fc polypeptide. Claim 2, line 2, is vague and indefinite because it recites “60°C or higher” and there is no upper limit to the temperature limitation recited in the claim. Similarly, claim 48, line 18, is vague and indefinite because it recites “60°C or higher” and there is no upper limit to the temperature limitation recited in the claim. Claim 11, lines 5, 7, 9, is vague and indefinite because it recites the limitation “and/or” and it is clear whether the limitation following “and/or” is part of the claimed invention. Similarly, claims 15, 19 is vague and indefinite because it recites the limitation “and/or” and it is clear whether the limitation following “and/or” is part of the claimed invention. Claim 23, line 3, is vague and indefinite because it recites the limitation “introduce cysteine residues capable of forming a disulfide bond”, however, it is unclear from the claim where the specific cysteine residues are introduced within a parent polypeptide, since the claim does not provide a parent polypeptide (amino acid sequence of specific SEQ ID NO), and therefore, it is impossible to determine where these cysteine residues would be introduced in the parent polypeptide. Similarly claims 24 and 25 are rejected as vague and indefinite because they recite “introduce cysteine residues”, however, it is unclear from the claim where the specific cysteine residues are introduced within a parent polypeptide, since the claim does not provide a parent polypeptide (amino acid sequence of specific SEQ ID NO). Claim 34, is indefinite because it recites the limitation “α-tailpiece”, without a reference SEQ ID NO. Claim 37, is indefinite because it recites the limitation “J chain”, without a reference SEQ ID NO. Claims 30-33, 36, 38-45, and 49, are rejected as vague and indefinite insofar as they depend on the above rejected claims for their limitations. Conclusion No claim is allowed. Claims 1-12, 14-16, 18-20, 22-25, 27, 30-45, and 48-49 are rejected. Advisory Information Any inquiry concerning this communication or earlier communications from the examiner should be directed to PREMA MARIA MERTZ whose telephone number is (571)272-0876. The examiner can normally be reached on Monday to Thursday from 7:30am to 6:00pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, VANESSA FORD, can be reached at telephone number 571-272-0857. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from Patent Center. Status information for published applications may be obtained from Patent Center. Status information for unpublished applications is available through Patent Center for authorized users only. Should you have questions about access to Patent Center, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) Form at https://www.uspto.gov/patents/uspto-automated- interview-request-air-form. /PREMA M MERTZ/ Primary Examiner, Art Unit 1646
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Prosecution Timeline

Jun 05, 2023
Application Filed
Jan 12, 2026
Examiner Interview Summary
Jan 12, 2026
Examiner Interview (Telephonic)
Feb 17, 2026
Non-Final Rejection — §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
72%
Grant Probability
99%
With Interview (+35.6%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 754 resolved cases by this examiner. Grant probability derived from career allow rate.

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